Force usage of dedicated GPU for OpenGL with Delphi and FreePascal/Lazarus on Multi-GPU systems such as Notebooks on Windows

ForceDedicatedGPUUsageForOpenGL.pas

// Force usage of dedicated GPU for OpenGL with Delphi and FreePascal/Lazarus on Multi-GPU systems such as Notebooks on Windows
// Insert that into your main source file, which is for example the .dpr (Delphi) or .lpr (Lazarus) file

{$define ForceDedicatedGPUUsage} // then you can uncomment and recomment this line, for compile-time-switching between 
                                 // integrated GPU and dedicated GPU
                                 
{$if defined(Windows) and defined(ForceDedicatedGPUUsage) and (defined(cpu386) or defined(cpux64) or defined(cpuamd64))}
{$ifdef fpc}
 {$asmmode intel}
{$endif}
procedure NvOptimusEnablement; {$ifdef fpc}assembler; nostackframe;{$endif}
asm
{$ifdef cpu64}
{$ifndef fpc}
 .NOFRAME
{$endif}
{$endif}
 dd 1
end;

procedure AmdPowerXpressRequestHighPerformance; {$ifdef fpc}assembler; nostackframe;{$endif}
asm
{$ifdef cpu64}
{$ifndef fpc}
 .NOFRAME
{$endif}
{$endif}
 dd 1
end;

exports NvOptimusEnablement,
        AmdPowerXpressRequestHighPerformance;
{$ifend}